Expansion bracelet with adjustable tension means for the springs



April 2, 1957 A. M. ANDERSON EXPANSION BRACELET WITH ADJUSTABLE TENSION MEANS FOR THE SPRINGS Filed Jan..28, 1954 4 INVENTOR. .fl/van M finders 0/7 ATTORNEYS United States Patent EXPANSION BRACELET WITH ADJUSTABLE TENSION MEANS FOR THE SPRINGS Alvan M. Anderson, Barrington, R. E.

Application January 28, 1954, Serial No. 406,730 2 Claims. or. 59-79 This invention relates to expandable linkage such as may be used for a bracelet.

Expansion linkage such as that which is the subject of this invention is utilized largely as a wrist watch attachment although it may also be used in conjunction with identification plates, lockets, or other articles of utility or adornment. Bracelets of this character in the past have had all of the working parts manufactured from metal, such for instance as brass, stainless steel, gold fill, or silver strips. The expansion linkage may be either of two types in which there is a so-called threepoint suspension or a two-point suspension, the threepoint suspension usually being used for the Wider mens bracelet and the two-point suspension frequently being used for the narrow womens bracelets. The present invention relates to both types of suspensions.

The linkages may be connected by means of separate eyelets to provide the basic extendable linkage which requires considerable assembly operations, and thus the assembly is an important cost factor. The linkage may also be approached from a difierent standpoint in which one of the members, frequently called the male or post member or the lower link of the series, has posts or eyelets drawn of the same piece of material in the form of extruded tubes from the flat stock of the link by a series of drawing operations. These drawing operations are performed in combination tools of very complicated design which require that the tools be extremely accurate in order that uniform parts may be formed. In this case the tools are exceedingly expensive to construct and maintain due to frequent repairs, and many duplicates are required in order that a continuous flow of parts of any given design may be had. This latter construction reduces the assembly cost, but the tools which are required are a material cost factor.

In each case above recited in the past there has been required a decorative shell formed for a bottom cover, this shell covering up the open ends of the exposed tubes drawn from flat stock or the loose eyelets or tubular rivets described above. These backs or shells which extend over the male post or lower link member also act as stops for one end of the activating coil springs which keep the series of parts in contracted position.

The back shells which are thus utilized contact the wrist of the wearer and are subject to considerable corrosive action from body acids, perspiration, and so forth, which tend to discolor the links and to erode them to a point where they lose their decorative and useful value. In some cases stainless steel is used for this bottom shell, and it has been found that stainless steel causes an inflammation or irritation of the skin of some people.

One ofv the objects of this invention is to eliminate the necessity of providing a back shell or cover for the male bottom or lower link of the expandable linkage, thus eliminating the need of assembling of such shell on the bracelet, which is a material cost factor.

Another object of the invention is to provide a stop ice for the coil spring in the recess or opening which receives it rather than relying upon a back shell to provide a stop for one end of the spring.

Another object of the invention is to mold the male, post or lower member from a material which will provide the posts required in their desired shape without further machine operations.

Another object of the invention is to provide the male, post or lower member from any colored non-metallic material which may be desired.

Another object of the invention is to lighten the weight of the bracelet by forming the linkage from one or more non-metallic links.

Another object of the invention is to reduce or eliminate the noise which may occur in metal parts sliding one over the other in the expansion of the linkage by the use of one or more non-metallic links arranged so that there is no metal to metal rubbing as expansion occurs.

Another object of the invention is to simplify the assembly, such for instance as by minimizing the manipulation which may be required for the positioning of the springs in place and thus reduce the assembly time required.

Another object of the invention is to eliminate the final finishing operation on the lower link which has heretofore been provided by bufling, polishing, or the like by reason of the lower link coming from the mold in a shiny and finished condition.

Another object of the invention is to provide a structure which will permit of a wide range of designs and yet a functioning of the bracelet in the desired manner.

With these and other objects in view, the invention consists of certain novel features of construction as will be more fully described and particularly pointed out in the appended claims.

In the accompanying drawings:

Figure 1 is a top plan view of the expandable linkage completed and in contracted position;

Figure 2 is a view similar to Figure 1 showing the linkage expanded;

Figure 3 is a plan view of the contracted linkage with the top shell removed;

Figure 4 is a perspective view of the spring;

Figure 5 is a perspective view of the upper link;

Figure 6 is a perspective view of the lower link;

Figure 7 is a perspective view of the upper and lower links and spring of Figures 4, 5, and 6 assembled; v

Figure 8 is a sectional view through the center of one pair of links as shown in Figure l on line 8-8;

Figure 9 is a section on line 9-9 of Figure 2;

Figures 10 is a section on line 10-10 of Figure 1, which is also represented as 10-10 in Figure 3 where the top shell is omitted;

Figure 11 is a view similar to Figure 2 but showing a modified form or" construction, that shown in Figure 11 being the two-point suspension type of expandable linkage as distinct from the three-point shown in the other views;

Figure 12 is a fragmental perspective view of a modified upper or female link.

In proceeding with this invention, I mold from ,nonmetallic material the basic linkage which is to form the expandable linkage of this invention. This will consist of a lower, male or post link which will be of a solid construction with posts extending upwardly therefrom, one of which will be hollow to receive a spring. I will also mold from non'metallic material a female, upper link or washer with openings which will receive the posts of the lower link. A spring may be dropped into a recess in the lower link and have one of its ends held while the other end of the spring will engage a lug or some holding means on the upper link and will move the links to contracted position. In the two-point suspension type of link, each of the two posts will be recessed andtwo springs will be employed to move the links to contracted position. In each case the lower or post link will have its bottom surface so formed that it will be smooth and finished and no shell need be provided for covering the same. A shell, however, is contemplated to cover the spring and working parts of the upper link to provide an ornamental upper surface. However, by the elimination of the assembly of a shell over lower link, a great saving is effected from a standpoint of assembly, and a linkage having the advantages above pointed out in the objects of the invention is accomplished.

With reference to the drawings, the lower post or male link is designated 12; (Fig. 6) and is molded into desired shape. It comprises a solid body of elongated shape designated generally 13 from which solid posts lid extend upwardly adjacent its opposite ends while a hollow post 15 extends upwardly from its middle portion which is provided with a cylindrical recess as at in having grooves or slots 17 extending axially and located at convenient spacings about the recess, four in number being shown in the embodiment of this invention, that adjustment of spring tension may be provided only one slot being used. The outer surface 18 (Fig. 8) of this lower link is smooth and of a finished construction requiring no further opera tion after it leaves the mold. The link is formed of a non-metallic material which will be molded into the shape here described. Polyethylene or any suitable resin having an opening at its center 22 of a size to receive and be pivotally mounted upon the post 15 or" link 12, while adjacent its opposite ends there are openings 23 each of a size to receive through it the post 14 of the lower link 2. The link 24 is formed of non-metallic material the same as the link 12 and will be molded into finished shape. Lugs 24 of generally L-shape with the hook portion extending inwardly are located intermediate the holes 22 and 23 for holding the tail of the spring in place. In'some cases instead of lugs 2d a recess 24 may be provided to receive the tail of the spring.

The spring is designated generally comprising a coil body 26 with one endof the coil extending tangentially therefrom as at 27 and the other end of the coil extending tangentially therefrom as at 28.

To assemble the linkage, a pair of links are first assembled such as shown in Figure 7 without a spring in which the bearing opening 22 is passed over the post and then this post is headed as at .79 shown Figure 8 to prevent detachment of this pair of links. Another pair of links are then assembled with a post lid of the lower link extending through opening 23 of the first assembled pair and the opening 23 of the second assembled pair extending over post 14 of the first pair and then the center post of the second pair and the post id of each pair are headed three at a time to assemble the second pair with the first pair. The third pair would be added similarly. The spring is then assembled by positioning the helical coil 26 into the recess lie with the short end 27 located in one of the slots 17. The long end or tail 23 of the spring is then twisted to possibly tension the coil '26 a little more and then lodged back of one or". the lugs 24 as shown in Figure 7 or put in recess 24' in Figure 12. Should the linkage then be expanded from the position shown in Figure 1 to the position shown in Figure 2 the springs will be placed under tension and will move the links back to contracted position such as shown in Figures 1 and 3.

The completion of the links is by placing a shell 30 over the top of the upper link, the shell being so formed that it will contact the lugs or hooks 24 as shown in Figure 10 and the fingers are rolled beneath the link as at 31 so as to hold the shell in place. In this case the shell is held in position on the upper link but is prevented from telescoping too far over the edges of the upper link by the hooks or lugs 24. No shell is required to be assembled on the lower link, and the bracelet is thus completed.

The shells 30 will probably be of metal although these shells may also be of a non-metallic material and positioned in place and there cemented by some suitable adesive to assemble the shell in place.

in the two-point suspension type of bracelet the links 35 are provided with two posts 36, one at either end, and a connector link 37 having openings 38 at each end is positioned over the posts of two links 35 to form the connection between them. Each of the posts in this case will have slots or grooves 39, and a spring such as that heretofore described may be positioned in the recess 4d with the short tail in the slot 39, and then this spring may be tensioned and placed back of a hook or lug 41 which is formed on the upper side of the upper link or washer or connector 37. A spring will beplaced in each of: the recesses in each of the posts 36 for the tensioning of this two-suspension type of expandable linkage. In this case the post member will be formed. of a solid block of material with the posts integral therewith and headed over the same as in Figure 8 and the springs will be similarly assembled. A top shell will also be placed over each of the upper links 37 in a manner similar to that heretofore described. No back shell will be required. In assembly, a washer or connector link 35 will be placed over the studs 36 of two posts links and then these posts will be headed simultaneously.

While the foregoing description mentions molding the basic male lower link from non-metallic material, it is to be understood that any suitable material which is either metallic or non-metallic may be utilized without departing from the spirit of the invention as defined in the appended claims.

I claim:

1. An expandable linkage comprising a series of elongated upper links and a series of elongated lower links, the links of one series having an opening therethrough and the links of the other series having an integral post extending through said opening to pivotally interconnect the upper links to the lower links, said post having a recess therein with a plurality of slots in the wall of said recess, a coiled spring in said recess with a tail end extending into any selected one of said slots to anchor it in position with desired adjustment of spring tension and with its other end engaging the other link to maintain the links in retracted position.

2. An expandable linkage as in claim 1 wherein the slot extends but partly through the post from the inner sur' face outwardly.

References'Cited in the file of this patent UNITED STATES PATENTS 2,334,622 Greenberg Nov. 16, 1943 2,433,766 Kubice Dec. 30, 1947 FOREIGN PATENTS 258,932 Switzerland June 1, 1949 

